Where does “k-jɔːʔ” come from?

k-jɔːʔ (Proto-Vietic) comes from Proto-Mon-Khmer kjaal.

Ancestry of “k-jɔːʔ”, step by step

Step	Language	Word	Meaning
1	Proto-Mon-Khmer	kjaal	—

k-jɔːʔ — Etymology, Origin & Word History | Etymology Explorer